Indications and Rationale for Use of Vascularized Fibula Bone Flaps in Cervical Spine Arthrodeses

Abstract

Anterior cervical spine arthrodesis for large defects using autograft or allograft fibula for anterior structural support is a widely accepted procedure. In unique demand situations, a vascularized fibular flap is regarded as an "improvement" to the standard procedure. While a vascularized flap does deliver living tissue to the region, it does so with added potential morbidity and increased technical demand. The indications in the literature for this procedure have not been clearly defined. In this article, the authors review specific high-demand situations where they believe a vascularized flap is indicated. They also review patient outcomes after this procedure. Fibular free flaps were used in six patients with failed previous cervical spine arthrodeses. Three of the six patients had preoperative radiation therapy, and one received postoperative radiation treatment. All six patients had tumor and/or osteomyelitis present. One patient died of intraoperative hypotension 3 days after a successful free flap transfer during an elective posterior spine instrumentation procedure. One flap was lost from a venous thrombosis, and the patient was then treated successfully with a second fibular free flap. Clinical and radio-graphic evidence of fusion was obtained at 3 months in the five surviving patients, and neurologic function remained stable or improved. Analyzing their results and the literature, the authors propose that fibular free flaps are indeed a useful adjunct in difficult cervical spine stabilization procedures. Indications for this flap include combinations of the following situations: failed prior attempts at fusion, anterior cervical arthrodeses of three or more vertebral levels, osteomyelitis of the spine, and tumor cases when the spine has been or will be radiated.